Grinding and mixing apparatus



July 15, 1930. I R. o. CHILD 7 1,770,459

GRINDING AND MIXING APPARATUS Filed July 1. 1929 2 Sheets-Sheet l July 15, 1930. R. o. CHILD 1,770,459

GRINDING AND MIXING APPARATUS Fiiled July 1, 1929 2 Sheets-Sheet 2 129.5. ell! 7/! Patented July 15, 193% TES as ea REGINALD OSWALD CHILIQOF HABROW, ENGLAND, ASSIGNOB 110 D. ANDERSON & SONS LIMITED, OF LONDON, ENGLAND GRINDING AND MIXING APPARATUS Application filed July 1, 1329, Serial No. 374,991, and in Great Britain July 20, 1928.

This invention relates to apparatus applicable for grinding and mixing various substances and rendering the same in solid, semisolid, liquid or other consistency and for combining materials of various densities with chemical or other constituents; the object being to enable the grinding and mixing to be accomplished more thoroughly quickly and completely than with the apparatus at pre- 10 sent available and to heighten the degree of uniformity of the product.

According to this invention, the apparatus comprises a pair of beaters each approximatingthe form of a propeller, the arrangement of the blades being such that those pertaining to the one beater or propeller have a righthand inclination or pitch and those of the other have a left-hand inclination or pitch. These beaters or propellers are mounted a suitable distance apart in a vessel or container preferably of cylindrical formation and adapted for rotation therein. The means for rotatively operating the beater de Vice is of such a character that the speed of rotation may be varied or a differential rotative movement or speed imparted to the beaters or propellers.

The beaters or propellers depend centrally and vertically into the vessel or container in which they are supported by means of a suitable upper structure or other convenient device and a spider-like stay in the vessel, ball or other antifriction bearings being pro vided for enabling high speed working to be attained. In the vessel or container and arranged vertically near the sides thereof there are fitted two or more breaker bars having serrated edges along a length thereof approximately equivalent to the depth of the beaters or propellers. These bars are formed with a concave inner face and the edges are of a cutting nature. The setting of the bars in relation to the beaters 0r propellers is such that they have the eifect of returning the material being treated to the beaters or propellers while the latter owing to their oppositely arranged pitch cause the material to be forced from the one to the other. For cooperation with the beaters or propellers and 5c the breaker bars, there is mounted on the walls of the vessel or container a series of vertically arranged l. or angle irons, these being of such dimension and disposition that they impart a breaking-up action to the material under treatment and throw it back upon the beaters or propellers.

The vessel or container may be formed with a jacket adapted for the circulation or otherwise of a cooling or heating medium and the beaters or propellers may be mounted in such a manner as to be adjustable relatively and with respect to their position in the vessel or container.

Suitable means for controlling the admission and exhaustion of the material may be provided in connection with the vessel or container and for supplying the cooling or heating medium to the jacket.

The actuating gearing or mechanism for the beaters may be, as above mentioned, contained in an upper frame structure or be arranged independently of the mixing vessel or container. In some instances, the gearing may be carried by suitable supports attached to'the vessel. y

In order that the invention may be readily understood and carried into effect, same will. now be more fully described with reference to the accompanying drawings, in which Figure 1 is a View showing the vessel or container in vertical section, on line 11 in Figure 2, and a belt pulley mounted in an upper structure for transmitting motion to the beaters or propellers.

Figure 2 is a corresponding plan of the vessel, the upper structure being indicated in broken lines.

Figure 3 is a view similar to Figure 1 showing an upper structure provided with two belt pulleys whereby oppositely directioned rotation may be imparted to the beaters and means for efiecting their adjustment.

Figure 4 is a detached view showing an alternative arrangement for effecting the aforesaid adjustment.

Figure 5 is a fragmentary view illustrating a crescent shaped serrated bar for use in the grinding and mixing apparatus of the invention.

a (0 indicate beaters which are approximately in the form of a propeller, the blades of the respective devices being oppositely arranged so that the blades of the one are of right-hand. inclination or pitch and the blades of the other of left-hand inclination or pitch. A pair of such heaters or propellers are shown in the illustration but it will he understood that the number may be increased if desired. By so arranging the blades, the heaters or propellers co-operate very successfully in completely grinding and mixing the material supplied to the vessel or container 7) in which they are adapted to work. The vessel or container is preferably of cylindrical formation and the shaft or shafts on which the heaters or propellers are mounted depends or depend into the vessel or container and is or are adapted for rotation by any suitable means. In the example shown. the leaters are arranged for working at differential speeds, the beater a being mounted on a hollow shaft 0 and the heater (1' on a shaft 0 which extends through the shaft 0. Rotative motion is imparted to the said shafts 0, 0 through gearing, such as indicated at c, 0", d, d', operatively connected with a belt pulley (l keyed to a shaft d; the whole working in a frame-like structure e bolted or otherwise attached to a carrying plate f which rests on piers or supports g. Rotating means of any other suitable character to that shown may be employed so that the heaters may be operated at the same speed or so that the speed may be varied and, if desired their rotation be effected at differential speeds, the shaft or shafts and the heaters being arranged and mounted in a manner suitable for operation in accordance with requirements.

It will be seen that the shaft 0 c in the illustration, are supported in a vertical attitude by the upper structure 0 and a spider support I)" or equivalent device, in the vessel 6. Ball or other anti-friction bearings may be contained in the bloc is h and i or one of them, and also in the hub of the support 6, the arrangement preferably being of a kind adapted to maintain the heaters in the operative position in the vessel 6 at a high rate of speed. If desired the heaters or propellers a a may be adjustably mounted so that their position relatively and in the vessel may be varied.

k is are vertically disposed bars which are formed with concave inner faces or assume a crescent shape in cross section, the edges being serrated or sharpened as at figure 5 for a portion of their length equivalent or thereabouts to the depth of the heaters and these bars are so set or rendered capable of adjustment in relation to the heaters that they co-operate therewith in causing the material to he returned to the heaters whose operation on the material cause the latter to be forced from the one heater to the other as the result of the action of the oppositely inclined blades.

Z Z are vertically arranged angle irons of L section for the purpose of imparting a breaking-up effect 011 the material under treatment and of throwing the same back for repeated action thereon by the heaters or propellers.

The vessel or container 6 is shown as formed with a jacket 6 into or through which a cooling or heating medium may be supplied or circulated. Any suitable or convenient means (not shown) may be provided for controlling the admission and exhaustion of the material to and from the vessel or container and for supplying or circulating the cooling or heating medium to or in the aforesaid jacket.

The operating gear or mechanism for the beater shaft or shafts may be arranged independently of the vessel and together with the said shaft or shafts be adapted for ready insertion into and removal from the vessel 1).

Referring to Figure 3, the upper structure comprises two stages 6, e" whereof the one 6" is provided with hearings h, h for the shaft 0 whereon the pulley d is keyed or otherwise operatively mounted; the said shaft 0 extending upward into the part e. of the upper structure where it is housed in a hearing it and terminates in a head 0* whereby it is adapted for rotation on balls (not shown) inserted in a ball race between that head and a corresponding head part at on the rotatable fitting n which houses the shaft 0. The upper end of the shaft 0 is taken through the said fitting a, and passes through the top plate 6 of the stage 0' where its emergent end is provided with a square or turning head 0"; the part of the shaft 0 which passes through the fitting n being a screw threaded on at a, for a purpose hereinafter descrihed, and held therein by a set screw n. The said fitting a has the pulley d keyed or otherwise operatively mounted thereon and a terminating head part m which works on balls (not shown) between the same and the top plate 8'.

The heater a is keyed as at a to the shaft 0 and is further secured thereto by the set screw a. Similarly, the beater a is keyed at as a to the shaft 0 and further secured thereto by the set screw a. The position of the beater a is thus fixed, the boss of the propeller-like formation thereof being set against the abutment or collar 0 on the shaft 0. The position of the beater a in relation to the beater a is, however, rendered variable by means of removable collars p which are adapted for application to the shaft 0' and the latter is arranged for vertical movement in the fitting n by means of the screwthreaded end indicated at 0. By means of the square or turning head 0' the shaft 0' may he raised or lowered and according to the number of collars p placed thereon the distance of separation of the two heaters may be adjusted to suit requirements, the shaft 0' being retained in the adjusted position by means of the set-screw a. Any collars p removed from their position between the heaters may be placed on the shaft 0' beneath the lower beater a and secured by the locking nut g, a spring washer being applied for the purpose of insuring rigidity owing to the high speed of rotation in working the apparatus. The upper end of the said shaft 0 is secured by the lock nuts inclicated at g. A pulley d is operatively related to the shaft 0 and, seeing that the pulley (5* is operatively related to the shaft 0, it will be readily understood that the said shafts are adapted for rotation in opposite directions.

Referring to Figure 4, the beater or propeller-like device a is fast on the shaft 0 in a manner already described with reference to Figure 3, while the beater a is similarly fast on the shaft 0', there being an abutment or collar 0 on the latter. Adjustment of the heaters in this construction is effected by operating the shaftc rotatively by means of the turning head 0 and so operating the screw-threaded portion 0 of the said shaft in the fitting n in a manner that will be readily understood.

With the improved apparatus, it is found that more complete homogeneity is obtained, apparently due to the fact that in the grind ing and mixing, as, for instance, in dealing with paint-like and similar materials, maximum absorption is secured, so that materials of heavy density when in admixture with materials of less density are rendered less susceptible to gravitation.

I claim 1- 1. Grinding and mixing apparatus comprising in combination a pair of heaters constituted of propeller blades of right and left hand inclination respectively pendently mounted in superposed adjustable relation in a jacketed vessel on shafts arranged one within the other and adapted for rotative opera tion at varying and dilferential speeds, a plurality of stationary vertical bars of crescent shape in cross section and having the sharpened edges thereof serrated arranged in cooperative relation with the said heaters and a plurality of stationary vertical angle irons of L section also arranged in cooperative relation with the said heaters to return the material under treatment from the walls of the vessel for further treatment by the heaters.

2. Grinding and mixing apparatus comprising in combination a acketed vessel or container for the material to be treated, a pair of shafts arranged the one within the other and depending into the said vessel, a heater on one of the shafts having propeller blades of righthand inclination, a similar beater on the other of said shafts having propeller blades of lefthand inclination, the said beaters being arranged in superposed relation, a bearing sup port for the said shafts, stationary vertical bars of crescent shape in cross section having serrated cutting edges for co-operating with the heaters, stationary vertical angle irons of L section for returning the material to the action of the heaters, means for adjusting the heaters relatively to each other and means comprising a driven pulley and differential a plurality of bars extending longitudinally of the vessel, the said bars being crescent shape in cross section and having the sharpened edges thereof serrated.

l. Grinding and mixing apparatus comprising a vertical vessel, a shaft extending downwardly into said vessel, heaters adjustably mounted on the end of said shaft, said heaters consisting of propeller blades, the successive blades of the propeller being oppositely pitched, driving means for rotating said shaft, and a plurality of bars extending longitudinally of the vessel, the said bars being crescent shape in cross section and having the sharpened edges thereof serrated.

In testimony whereof I have subscribed my signature this 17th day of June, 1929.

R. O. CHILD. 

